function [descriptor] = getDescriptor(border, n)
%GETDESCRIPTOR Return 'n' values from the descriptor of the given border
% 'border'

% We calculate the complex coordinates of the border
real = border(1, :);
imaginary = border(2, :);
complexBorder = complex(real, imaginary);

% Execute the Fourier Transform and get the absolute values
descriptor = fft(complexBorder);
absDescriptor = abs(descriptor);

% We divide all the coefficient by the second descriptor to get
% magnification invariance
descriptor = absDescriptor(3:size(absDescriptor, 2))/absDescriptor(2);

% We select only the requested values
descriptor = descriptor(3:n-3);

end

